The process of removing naturals (oil, wax, fats, gum etc) as well as added impurities (during fabrication process) to produce hydrophilic and clean textile materials is called scouring. It is very vital process of wet processing.
Objectives of Scouring:
The main purpose of scouring is to remove impurities from the textile materials.
To make the fabric highly hydrophilic.
To make the textile materials in a highly absorptive condition without undergoing chemical or physical damage significantly.
To produced a clean material by adding alkali.
To remove non-cellulosic substance in case of cotton.
To make the textile material suitable for the subsequent bleaching operations.
Changes occurred during scouring:
Free fatty acids are converted into soap.
Proteins are hydrolyzed into soluble products.
Pectose and pectin are changed into soluble salts of pactic acid.
Mineral matter is dissolved.
Dust particles are removed.
Residual sizing materials are broken down into soluble products.
Scouring process depends on:
Types of fabric.
Color of fabric.
Cleanliness of fabric.
Twist of the fabric.
Count of the fabric.
Construction of the fabric.
Methods of scouring: Two methods are available. They are: